Three more Japanese reactors step closer to restart

25 August 2017

Japan's nuclear regulator today approved the 'construction plans' for strengthening Ohi units 3 and 4 and Genkai unit 3. The plans are the second of three applications required during the restart process. The units must undergo further inspections before being permitted to restart.

Ohi units 3 and 4 (Image: Kansai)

Under Japan's reactor restart process, plant operators are required to apply to the Nuclear Regulation Authority (NRA) for: permission to make changes to the reactor installation; approval of its construction plan to strengthen the plant; and, final safety inspections to ensure the unit meets new safety requirements. Operators are required to add certain safety-enhancing equipment within five years of receiving the NRA's approval of a reactor engineering work program.

Kansai Electric Power Company submitted its construction plan application for units 3 and 4 of its Ohi plant in Fukui prefecture to the NRA in July 2013. It supplemented this application with additional information the following month and subsequently submitted five amendments.

The construction plan for unit 3 of Kyushu Electric Power Company's Genkai plant in Saga prefecture was also submitted to the NRA in July 2013. The company subsequently made four amendments to the application. In January this year, the NRA confirmed Genkai 3 and 4 - both 1180 MWe pressurised water reactors - meet new regulatory standards.

With the NRA now approving these plans, both companies said they now plan to apply for pre-operation inspections of those units. These inspections are to confirm that the safety countermeasure equipment complies with the approved construction plan at the plant.

Kyushu said it also plans to submit a construction plan for unit 4 at the Genkai plant.

Of Japan's 42 operable reactors, five have so far cleared inspections confirming they meet the new regulatory safety standards and have resumed operation. These are: Kyushu's Sendai units 1 and 2; Shikoku's Ikata unit 3; and, Kansai's Takahama units 3 and 4. Another 19 reactors have applied to restart.